complete conductivity
71Sand casting — Sand casting, also known as sand molded casting, is a metal casting process characterized by using sand as the mold material. It is relatively cheap and sufficiently refractory even for steel foundry use. A suitable bonding agent (usually clay)… …
72Electrolysis of water — is the decomposition of water (H2O) into oxygen (O2) and hydrogen gas (H2) due to an electric current being passed through the water. Simple setup for demonstration of electrolysis of water at home. Contents …
73amorphous solid — ▪ physics Introduction any noncrystalline solid in which the atoms and molecules are not organized in a definite lattice pattern. Such solids include glass, plastic, and gel. Solids and liquids (liquid) are both forms of condensed… …
74hydrologic sciences — Introduction the fields of study concerned with the waters of the Earth. Included are the sciences of hydrology, oceanography, limnology, and glaciology. In its widest sense hydrology encompasses the study of the occurrence, the… …
75chemical bonding — ▪ chemistry Introduction any of the interactions that account for the association of atoms into molecules, ions, crystals, and other stable species that make up the familiar substances of the everyday world. When atoms approach one another …
76Alkane — Not to be confused with Alkene or Alkyne. Chemical structure of methane, the simplest alkane Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded… …
77Chemical bond — A chemical bond is an attraction between atoms that allows the formation of chemical substances that contain two or more atoms. The bond is caused by the electromagnetic force attraction between opposite charges, either between electrons and… …
78Vacuum — This article is about empty physical space or the absence of matter. For other uses, see Vacuum (disambiguation). Free space redirects here. For other uses, see Free space (disambiguation). Pump to demonstrate vacuum In everyday usage, vacuum is… …
79Joseph Priestley — (13 March 1733 (Old Style) – 6 February 1804) was an 18th century British theologian, Dissenting clergyman, natural philosopher, educator, and political theorist who published over 150 works. He is usually credited with the discovery of oxygen,… …
80Stirling engine — Alpha type Stirling engine. There are two cylinders. The expansion cylinder (red) is maintained at a high temperature while the compression cylinder (blue) is cooled. The passage between the two cylinders contains the regenerator …
